MNF Utility Codes

MNF Utility Codes

Several types of utility programs are essential to the efficient use of mloc. These include programs for converting arrival time datasets to mloc’s native data format (MNF) and a program for extracting event files from MNF-formatted bulletins (concatenations of event files). The source codes for these utilities are contained in the mloc distribution in the directory /mloc_distribution/mnf_utilities/. See MLOC Utility Codes for some other important utility programs.

Data Format Conversion Codes

These programs convert files written in two of the most commonly encountered data formats for arrival times. Contact me if you need help with conversion from other formats.


isc_ims2mnf handles conversion to MNF format from the version of the IMS format returned by the bulletin search function of the ISC website. The process for acquiring data from the ISC Bulletin is described here. This will usually be a bulletin, i.e., many events in a single file. To convert the bulletin to MNF, copy the executable of the program isc_ims2mnf into the same directory and run it. The only input is the name of the IMS-formatted file. The output will have the same name with “.mnf” appended.

Warning! If the search of the ISC Bulletin has used a condition on magnitude there will be a line near the top of the file listing that condition. The conversion program will try to process that line as being part of an event and crash. The solution is simple: add an “#” to the beginning of that magnitude condition line.

Once the bulletin is converted to MNF format, use the program mnf_search to extract individual events for relocation in mloc.


This program handles conversion to MNF from the “nordic” format produced by SEISAN. SEISAN is widely used by local and regional seismograph networks around the world. Unfortunately, the formats of event data files produced by these many installations do not always agree in detail, causing erros in conversion or outright crashes. In such cases it is necessary to edit the code of seisan2mnf for use with data files from specific networks. In any case it is always advisable to do a careful examination of the converted data files afterward.

Codes to Manipulate Event and Bulletin Files

I have written a number of utility programs to carry out various editing and exploratory tasks on files (both single events and bulletins) formatted as MNF v1.3, but only one of them is used regularly in conjunction with mloc: mnf_search, a program for searching an MNF-formatted bulletin and extracting individual event files for input (using the inpu command, usually in a command file). The source code and an executable for macOS is found in /mloc_distribution/mnf_utilities/mnf_search/.

  • mnf_search: search a bulletin in MNF format and extract events selected according to various criteria into a new bulletin or into individual event files (as used by mloc).

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